canoe yawl IRIS modifications

I recently came across this design in W.P. Stephens' Canoe & Boatbuilding for Amateurs, and really like the design. However I am thinking that a few modifications are in order, and I am hoping that I can tap into some of the groups more knowledgeable members for feedback on these changes.

First off I am considering increasing the general dimensions by 10%. I have read previously that this is an acceptable level of increase on most small craft without severely affecting the overall design. I will be working from very minimal plans provided in the book., which include the offsets, scantlings, and rig information along with the images below. I didn't think it would be much of a stretch since I will be lofting and head scratching on construction details anyway.

Secondly, I will be using modern construction techniques, most likely strip planking with a veneer over that, of possibly glued lapstrake. Any thoughts on the transition into modern materials and affects on weight, strength, etc.

Third, and probably my biggest question mark is the design and placement of a centerboard for improved windward ability. My ideal would be a fan design remaining below or just above the floor boards. Adding to the complexity is the position of the lead shoe that would need to be slotted for a centerboard. Any thoughts or directions on this would be greatly appreciated.

Lastly the rig. I like it just as it stands, a yawl with fully battented balanced lug, but would love to hear any comments on the design. It just seems like it would be a dead simple and inexpensive rig to produce. Maybe not as fast or versatile as others but well suited to this minimalist cruiser.

All comments and thoughts appreciated.

I have included the link to Iris below

Cheers!

Vaka Punahttp://freepages.genealogy.rootsweb.ancestry.com/~fassitt/canoe_mirror/cassy.html

 

The centerboard appears reasonably well positioned, considering the limitations of the rig, buttocks aft, aspect ratio and centers of sail plan and appendages, etc.

Strip planking then sheathing with lapstrake will make for a lot of extra work, a heavy boat and hide pockets for potential moisture and rot. If you want a lapstrake boat, convert it to glued lap construction, which will produce a light, strong boat that you only have to plank once, not twice.

Conversely, if you a smooth hull then strip plank is a well proven method. It's not as light as lap strake, but it's easier for the novice builder.

Canoe yawls by their very nature need to be lightly built, or they'll perform poorly. I wouldn't be especially concerned about windward ability, when building an antique boat of this general configuration. She'll do okay to weather, but don't expect miracles as this wasn't her intent 130 years ago.

 

I sure hope you build it. Keep us posted.Check out the following link
http:canoesailingmagainze.com